bcachefs: fix userspace build errors

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/bcachefs.h

@@ -193,6 +193,7 @@
 #include <linux/mutex.h>
 #include <linux/percpu-refcount.h>
 #include <linux/percpu-rwsem.h>
+#include <linux/refcount.h>
 #include <linux/rhashtable.h>
 #include <linux/rwsem.h>
 #include <linux/semaphore.h>

fs/bcachefs/bcachefs_format.h

@@ -2249,7 +2249,7 @@ static inline unsigned jset_entry_dev_usage_nr_types(struct jset_entry_dev_usage
 struct jset_entry_log {
 	struct jset_entry	entry;
 	u8			d[];
-} __packed;
+} __packed __aligned(8);
 
 /*
  * On disk format for a journal entry:

fs/bcachefs/btree_iter.c

@@ -2699,8 +2699,8 @@ void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src)
 void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
 {
 	unsigned new_top = trans->mem_top + size;
-	size_t old_bytes = trans->mem_bytes;
-	size_t new_bytes = roundup_pow_of_two(new_top);
+	unsigned old_bytes = trans->mem_bytes;
+	unsigned new_bytes = roundup_pow_of_two(new_top);
 	int ret;
 	void *new_mem;
 	void *p;